Many systems use switching regulators to produce regulated voltages for use by other components of the systems. In a buck or step-down regulator, the regulator produces an output voltage VOUT that is lower than its input voltage VIN. The output voltage VOUT can remain generally consistent or in regulation even as the input voltage VIN varies. However, one problem is that the buck regulator can suffer from dropout if its input voltage VIN becomes too low. During dropout, the input voltage VIN drops below some threshold voltage level, and the buck regulator can no longer maintain regulation of the output voltage VOUT. When that occurs, the output voltage VOUT follows the input voltage VIN, so further drops in the input voltage VIN cause corresponding drops in the output voltage VOUT.